UV/TiO2降解矿井水CODcr中SO4^2-,HCO3^-和Cl^-的影响及动力学研究  

Kinetics and Effect of SO_4^(2-),HCO_3^- and Cl^- in Coal Mine Water on Degradation of Mine Water CODcr by UV/TiO_2

作　　者：姚恩亲[1] 桂和荣[1] 

机构地区：[1]安徽理工大学资源与环境工程系,安徽淮南232001

出　　处：《稀有金属》2008年第2期224-229,共6页Chinese Journal of Rare Metals

基　　金：安徽省自然科学重点科研项目(2005KJ002ZD);安徽省自然科学基金项目(070414168)

摘　　要：探讨矿井水中SO42-,HCO3-和Cl-对TiO2光催化降解矿井水化学需氧量-铬法(CODcr)性能的影响。用阴离子树脂充分过滤掉矿井水中阴离子,再用Na2SO4,NaHCO3和NaCl分别配制其在矿井水中单一存在的浓度,使用自制的TiO2在紫外灯照射下光催化降解矿井水中CODcr。当3种离子单独存在时,它们均能使光催化CODcr的降解率下降,影响大小依次是HCO3->SO42->Cl-,在Cl-为低浓度4.45mmol·L-1对CODcr降解率有轻微促进作用。采用Langmuir-Hinshelwood机制分别研究了矿井水CODcr在SO24-,HCO3-和Cl-离子单独存时的光催化降解动力学,降解模式符合准一级反应动力学方程。在pH7.9~8.7和辐照强度为紫外光辐照强度70μW·cm-2条件下,含HCO3-矿井水的Kr为31·45mmol·L-1·min-1,Kb为0.56L·mmol-1;含SO42-矿井水的Kr为37.31mmol·L-1·min-1,Kb为0.779L·mmol-1;含Cl-矿井水的Kr为39.68mmol·L-1·min-1,Kb为0·739L·mmol-1。Effects of SO4^2-, HCO3^- and Cl^- in coal mine-water on performance of light-catalytic degradation of mine-water CODcr with TiO2 were discussed. Fully filtered the anions in mine-water with anion resin, then Na2SO4, NaHCO3 and NaCl in a certain concentration was added into the mine-waters, respectively to prepare the test mine-water. CODcr existed in the mine-water degraded light-catalytically with prepared TiO2 under ultraviolet light irradiation. Every one ion of the three kind of additive in the mine-water could decreased the rate of CODcr light-catalytic degradation and had the order of HCO3^-〉SO4^2-〉Cl^-, but Cl^- in 4.45 mmol·L^-1 the rate of CODcr degradation increased a little. Using Langmuir-Hinshelwood to study reaction mechanism on light-catalytic degradation of CODcr existed in the mine water contained SO4^2-, HCO3^- and Cl^- separately, their degradation kinetic mode was conformed to a quasi-first order kinetic equation. When pH was 7.9～8.7 and irradiation intensity was 70 μW·cm^-2, contained HCO3^- in coal mine-water, the Kr was 31.45 mmol·L^-1·min^-1 and Kb was 0.56 L·mmol^-1; contained SO4^2- of coal mine water, the Kr was 37.31 mmol·L^-1·min^-1 and Kb was 0.779 L·mmol^-1; contained Cl-of coal mine water, the Kr was 39.68 mmol·L^-1·min^-1 and Kb was 0.739 L·mmol^-1.

关 键 词：矿井水 TIO2 CODCR SO4^2- HCO3^- Cl^- 动力学 

分 类 号：X523[环境科学与工程—环境工程]